Pipe-welding plant



' 1,640,220 I Aug* 23 1927 J. H. SENNETT PIPE WELDING PLANT Filed June 23. 1923 2 Sheets-Sheet 2 Patented Aug. 23, 1927.

Laarne osi-"rsfv stares Arrreu'i" ortica.

.Toi-1N n'. snmvnrr, or'woontawiv, PENNSYLVANIA, Assreivon 'ro Joivns a LAUGHLN srs-En ooaeonafroiv, or Pfr'rsefonen, rmnvsi'nvarra, A conPoRA'IfoN 0F y rmnsvr'vanrn.

rirnwnnnrue PLANT.

My invention relates to improvements in plants for making'welded pipe and in methods of operation of suchplants. In an application for Letters Patent of Vthe United States, tile-,c December ll, 1920, Serial No. 429,853', in which Iam one of the joint .applicants, a plan for weldingl pipe' is shown and described. It is in the plant of that application that have developed and embodied. my present invention, and in such embodiment shall hererdescribe it. rIhis is a plant for making lapeweld steel pipe. lt will be understood that the invention may be embodied generally in the building of plants in which bent skelp is heated and welded. The object in view is economy in operation.

ln the accompanying' `drawings Fig. l is a view in plan of a pipe makingv plant in which my present invention is embodied. F ig; il* is af view to larger scale, showing in vertical and transverse section the furnace which is a` new elementinthe organizationv of the lplant and whose introduction and y coordination with other elements constitutes my present invention.V Theplane of sec- -tion of Fig. Il is indicated by the line fil-ll, Fig. I.

Referrin.0` tiret to Fi .I l 1s a` weldinff n n furnace and 2 1s aV weldino machine-f3 are D Y ,n troughs through whichy bent slelpv is advanced and'introduced into Ythe welding;`

furnace, and i are troughs through which' the welded pipe is delivered from the weld'- ing;r machine. 5 are the charging openings of the welding'furnace, 6 the delivery opening, and T the openings in the opposite `and remote furnace wall, through which worl-zmen have'access, for moving' the slielp upon the furnace floor, and through which pushing" apparatus, if such apparatus be desired, may enter, to drive Vthe skelp individually when heated` from the weld-Ling;A furnace through the delivery opening' 6 to the welding` machine 2. There are two gutters 8 in the floor' of the furnace,- and into these gutters the skelp under treatment is eventually dvanced and from them the skelp is pushed to the welding machine. rlhe two delivery.r troughs et are aligned with the Agutters 8 and the delivery opening' 6 in the furnacewall is wide enough to allow free passage of the slrelp between. rhe welding machine is movable laterally to alignment with either furnaces.

gutter and its corresponding delivery trough. y

In operation the bent sllelp are advanced on either side one by one in troughs o .Along gutters Sathe heated sk elp is pushed,

manually or by a mechanical pusher, rst along one gutter, then along the other, through the opening 6 and into the` welding machine. Therel the pi 3e is welded. From the weldfng machine tie welded pipe vances along; troughs't.

Further minute cescri'ption of other features of this particular plant are not important to a.v description of my present invention. They may however be found, set

forth in the specification above.- alluded to.

As described in thatearlier application, the benty slrelp are advanced sidewise over skids to position in the charging troughs.

The care and'. attention required by the skelp within furnace 1 is great. Thetemperature to whichfthe skelp must withinjthe welding furnace be' brought is about '2A-00 F. and that is a temperature far toohigh to admit of any ymechanical apparatus for dealingwitrh the slelp within the furnace,-roll ing them and. advancing` them to gutters 8. Itaccordingly necessary that the weldingl furnace be tended and that the slrelp within be advanced manually. The `turning down must be done by hand. i

I have perceived, and from this percept-.on springs my invention, that is only" tie slrelp' approaches weldin heat, that is to say, it is Vonly withv the higher rang-jes of the elevatedl temperature attained that the atA consists in cutting in two the skelp-heati operation, and in providing.)T two heating In one of the two furnaces the skelp is heated only to such degree as is not prohibitive of the use of mechanical conveying apparatus, while in the other furnacI which receives from the first the partially tenti'on ofthe turner down is required.A d based upon this perception, my invention heated slrelp, heating is completed under manual attention.

Referring` still to Fig. l of the drawings, my invention consists in providing two auxiliary furnaces 9, with charging openings on one side and delivery openings 11 upon the other side, into which bent slelp pass sidewise from slridways 12 and from which they pass sidewise to the troughs 3 which feed the furnace 1. These two furnaces 9 are symmetrically arranged one on either side of the mid-line of the welding furnace 1.

Fig. Il shows one of the two duplicate and complementarily arranged furnaces 9 in detail. It will be seen to be a furnace f simple rectangular shape with vaulted roof and long side openings. Suitable heating means are indicated in gas pipes 13 and ll.

An endless chain conveyor 15 equipped with slrelp-engaging fingers 16, advancing, automatically picks up the skelp one by one from the skidway 12, gradually advances them through the furnace chamber and delivers them one by one to the trough 3. The skelp are indicated by the letter s. Proper means may be provided for protecting the conveyor if need be from excessive heat as by the provision of a water-cooled conveyor skid 17, over which the reach of the conveyor 15 within the furnace chamber passes. The temperature control is such, and the speedof conveyor travel is such, that within the furnace 9 the skelp may be raised to a temperature of say 1200O to lll-00o F., a temperature range which is not so high, but that it is entirely possible and practicable to operate within the furnace a mechanical conveyor such as that which is illustrated in Figure Il.

The so preheated skelp, passing from the furnace 9 and delivered automatically over an incline 18 to the trough 3, is immediately and wit-hout any substantial loss of heat carried along trough 3 into the welding furnace 1. There within the welding furnace 1 the regular nornial operation is conducted with this modification, that now the attendant who takes care of the slrelp within the welding furnace has to take care of it through a much narrower range of temperature, and through a much shorter interval of time, and while the speed of production continues undiminished he has a very much diminished number' of skelp under his care at any particular instant of time. Proportionately as the number of skelp to be handled within furnace 1 is reduced and the operation within furnace 1 simpliiied, the number of attendants may be reduced, and the work which previously had to be' done wholly manually, is in part accomplished by the mechanical conveyor in the auxiliary furnaces 9. Herein and in consequence hereof there is a very substantial saving in cost of production, and an improvement in the economy and eihciency of the plant as a whole. Y

As I said at the beginning, l here show and describe my invention in its application to a pipe-welding plant of a particular construction and arrangement. Manifestly it is applicable in any plant wherebent skelp has to be raised to welding temperature.

claim as my invention: l

1. In a pipe welding plant the combination of a welding machine, a welding furnace provided with a turn-down opening adapted to deliver heated skelp to said welding machine, a preheating furnace adapted to receive bent slrelp and to heat the received slelp to a tempera-ture somewhat less than welding temperature, and means for conveying skelp in substantially direct course through said preheating furnace and into said welding furnace.

2. ln a pipe welding plant the combination of a welding machine, a welding furnace provided with a turn-down opening adapted to deliver heated skelp to said welding machine, a preheating furnace adapted to receive bent slelp and to heat the received skelp to a temperature somewhat less than welding temperature, means for conveying in substantially direct course from said preheating furnace and for charging into sa'id welding furnace slelp delivered from said preheating furnace, and means for conveying skelp in continuous course through said preheating furnace and to the first-named conveying means.

3. In the production of welded pipe the method herein described which consists in heating bent slrelp to a temperature approximating the limit of mechanical conveyance, mechanically conveying the so-heated skelp to the welding furnace, and completing in the welding furnace the heating of the skelp to welding temperature.

In testimony whereof I have hereunto set my hand.

JOHN H. SENNETT. 

